The drilling of oil and gas wells in an offshore environment typically requires the use manned drilling platforms over extended periods of time. In order to provide a hospitable environment for the personnel, it is necessary that these drilling platforms be provided with large quantities of potable water for use be the personnel manning the platforms. Providing such water typically involves providing large storage tanks for potable water, these tanks being replenished by water being brought the platforms, or providing bulky, cumbersome, desalination equipment that either utilizes valuable platform space or requires tender vessels to support the equipment. The present invention is designed to provide a high volume, portable desalination apparatus designed to eliminate those problems associated with providing potable water on drilling platforms.